From: Alan Lawrence <alan.lawrence@arm.com>
Date: Mon, 27 Oct 2014 15:53:25 +0000 (+0000)
Subject: [AArch64] Restore gimple_folding of reduction intrinsics
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=fc72cba7ce5bbd350249dd5de10bc9eaa1633a8e;p=gcc.git

[AArch64] Restore gimple_folding of reduction intrinsics

	* config/aarch64/aarch64.c (TARGET_GIMPLE_FOLD_BUILTIN): Define again.
	* config/aarch64/aarch64-builtins.c (aarch64_gimple_fold_builtin):
	Restore, enable for bigendian, update to use __builtin..._scal...

From-SVN: r216742
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a938d9dd2fc..8cdd603221f 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2014-10-27  Alan Lawrence  <alan.lawrence@arm.com>
+
+	* config/aarch64/aarch64.c (TARGET_GIMPLE_FOLD_BUILTIN): Define again.
+	* config/aarch64/aarch64-builtins.c (aarch64_gimple_fold_builtin):
+	Restore, enable for bigendian, update to use __builtin..._scal...
+
 2014-10-27  Alan Lawrence  <alan.lawrence@arm.com>
 
 	* config/aarch64/aarch64-simd-builtins.def (reduc_smax_, reduc_smin_,
diff --git a/gcc/config/aarch64/aarch64-builtins.c b/gcc/config/aarch64/aarch64-builtins.c
index 9652f1487e4..c8c99f16113 100644
--- a/gcc/config/aarch64/aarch64-builtins.c
+++ b/gcc/config/aarch64/aarch64-builtins.c
@@ -1207,9 +1207,6 @@ aarch64_fold_builtin (tree fndecl, int n_args ATTRIBUTE_UNUSED, tree *args,
   return NULL_TREE;
 }
 
-/* Handling of reduction operations temporarily removed so as to decouple
-   changes to tree codes from AArch64 NEON Intrinsics.  */
-#if 0
 bool
 aarch64_gimple_fold_builtin (gimple_stmt_iterator *gsi)
 {
@@ -1219,19 +1216,6 @@ aarch64_gimple_fold_builtin (gimple_stmt_iterator *gsi)
   tree fndecl;
   gimple new_stmt = NULL;
 
-  /* The operations folded below are reduction operations.  These are
-     defined to leave their result in the 0'th element (from the perspective
-     of GCC).  The architectural instruction we are folding will leave the
-     result in the 0'th element (from the perspective of the architecture).
-     For big-endian systems, these perspectives are not aligned.
-
-     It is therefore wrong to perform this fold on big-endian.  There
-     are some tricks we could play with shuffling, but the mid-end is
-     inconsistent in the way it treats reduction operations, so we will
-     end up in difficulty.  Until we fix the ambiguity - just bail out.  */
-  if (BYTES_BIG_ENDIAN)
-    return false;
-
   if (call)
     {
       fndecl = gimple_call_fndecl (stmt);
@@ -1243,23 +1227,28 @@ aarch64_gimple_fold_builtin (gimple_stmt_iterator *gsi)
 			? gimple_call_arg_ptr (stmt, 0)
 			: &error_mark_node);
 
+	  /* We use gimple's REDUC_(PLUS|MIN|MAX)_EXPRs for float, signed int
+	     and unsigned int; it will distinguish according to the types of
+	     the arguments to the __builtin.  */
 	  switch (fcode)
 	    {
-	      BUILTIN_VALL (UNOP, reduc_splus_, 10)
-		new_stmt = gimple_build_assign_with_ops (
+	      BUILTIN_VALL (UNOP, reduc_plus_scal_, 10)
+	        new_stmt = gimple_build_assign_with_ops (
 						REDUC_PLUS_EXPR,
 						gimple_call_lhs (stmt),
 						args[0],
 						NULL_TREE);
 		break;
-	      BUILTIN_VDQIF (UNOP, reduc_smax_, 10)
+	      BUILTIN_VDQIF (UNOP, reduc_smax_scal_, 10)
+	      BUILTIN_VDQ_BHSI (UNOPU, reduc_umax_scal_, 10)
 		new_stmt = gimple_build_assign_with_ops (
 						REDUC_MAX_EXPR,
 						gimple_call_lhs (stmt),
 						args[0],
 						NULL_TREE);
 		break;
-	      BUILTIN_VDQIF (UNOP, reduc_smin_, 10)
+	      BUILTIN_VDQIF (UNOP, reduc_smin_scal_, 10)
+	      BUILTIN_VDQ_BHSI (UNOPU, reduc_umin_scal_, 10)
 		new_stmt = gimple_build_assign_with_ops (
 						REDUC_MIN_EXPR,
 						gimple_call_lhs (stmt),
@@ -1281,7 +1270,6 @@ aarch64_gimple_fold_builtin (gimple_stmt_iterator *gsi)
 
   return changed;
 }
-#endif
 
 void
 aarch64_atomic_assign_expand_fenv (tree *hold, tree *clear, tree *update)
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 407026a6d22..bd82d1c56dc 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -10096,8 +10096,8 @@ aarch64_asan_shadow_offset (void)
 #undef TARGET_FRAME_POINTER_REQUIRED
 #define TARGET_FRAME_POINTER_REQUIRED aarch64_frame_pointer_required
 
-//#undef TARGET_GIMPLE_FOLD_BUILTIN
-//#define TARGET_GIMPLE_FOLD_BUILTIN aarch64_gimple_fold_builtin
+#undef TARGET_GIMPLE_FOLD_BUILTIN
+#define TARGET_GIMPLE_FOLD_BUILTIN aarch64_gimple_fold_builtin
 
 #undef TARGET_GIMPLIFY_VA_ARG_EXPR
 #define TARGET_GIMPLIFY_VA_ARG_EXPR aarch64_gimplify_va_arg_expr